While a mixed bag of results, oil companies continue to gain ground.

According to ExxonMobil's report, net income is at a near record high of $10.89 billion, which is an increase of 17 percent from the first quarter of 2007. Company Chairman Rex Tillerson noted earnings per share were up 25 percent, which reflects the impact of the continuing share purchase program. "Higher crude oil and natural gas realizations, driven by record worldwide crude oil prices, were partly offset by lower refining and chemical margins, lower production volumes and higher operating costs," he said in a released statement.

"Spending on capital and exploration projects was $5.5 billion in the first quarter, up 30 percent from last year, as we continued to actively invest in projects to bring additional crude oil, natural gas and finished products to market," Tillerson noted.

CNNMoney.com reported that upstream earnings for ExxonMobil's exploration and production units rose $2.74 billion to $8.8 billion, while refining and marketing profit in the company's downstream business fell $746 million to $1.17 billion.

Edward Jones Analyst Lanny Pendill told the online news service that the bright spot in ExxonMobil's report was commodity prices, however its adjusted six percent dip in total production raised questions about future output levels.

"With natural declines in production fields, they need big projects to move the needle, and those are harder to come by year after year," Pendill told CNNMoney. "Still, the oil giant's boost in capital spending could help out as far as production goes down the road." The report stated that Malaysia's national oil company, PETRONAS, signed the main principles agreement with ExxonMobil for a new 25 year production sharing contract, to further develop petroleum resources offshore Peninsular Malaysia. The contract includes commitments to implement significant enhanced oil recovery activities and for major investments to continue conventional oil development.

From its Houston headquarters, Marathon Oil Corp. reported a first quarter 2008 net income of $731 million. In comparison, net income for the first quarter of 2007 was $717 million. This year's first quarter net income adjusted for special items was $767 million, compared to net income adjusted for special items of $707 million, for the first quarter of 2007.

"Despite a very challenging downstream environment, our business overall generated very solid financial results for the first quarter, with increased adjusted net income over both the first and fourth quarters of 2007," Clarence P. Cazalot, Jr., Marathon president and CEO, said in a released statement.

Cazalot explained the company's upstream and integrated gas segments had strong operating performance and benefited as well from higher overall hydrocarbon prices. To this end, upstream sales volumes were up 11.5 percent on a year-on-year basis and 6.8 percent quarter over quarter, while Marathon's LNG facility in Equatorial Guinea performed at near full capacity.

"Downstream results were adversely impacted by lower overall margins as a result of rapidly rising crude oil prices as well as the substantial amount of planned maintenance we performed at two of our largest refineries in the first quarter," Cazalot noted in the report.

From its Calgary headquarters, Imperial Oil announced its first quarter net income earnings, which at $681 million, fell short of last year's first quarter earnings of $774 million.

"Despite a number of challenges faced during the quarter, Imperial remains in an enviable position as we continued to add to our inventory of high-quality development opportunities," Bruce March, Imperial CEO, said in a released statement. "The combination of financial strength, technology advantage, proven business model and superior mix of skills and assets set the stage for continued growth in shareholder value," he noted.

Imperial Oil's earnings were impacted by lower downstream earnings, the report stated. In the upstream, higher crude oil and natural gas commodity prices were partially offset by the negative impacts of lower conventional volumes from expected reservoir decline, lower Syncrude volumes, and higher royalties along with a stronger Canadian dollar. Upstream earnings were also negatively impacted by lower gains from asset divestments. The negative impacts of lower overall industry refining margins, unplanned shutdown at its Strathcona refinery and a stronger Canadian dollar contributed to lower downstreamearnings, the report stated.